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Contributions to this software library are always welcome. Please ensure that you post program listings rather than .raw files. They give a reasonable idea of what your program does without having to load them into a DM42 and you can also include comments in your code. Check out the following link for a decoder/encoder: http://www.swissmicros.com/dm42/decoder/

This one takes three arguments "Wet Bulb", "Dry Bulb" (thermometer) and the barometric pressure to calclulate the relative humidity in percent and the dew point in °C
Enter wet/dry temp in °C and the barometric pressure in mb.

Ex: Tw=22, Td=25, baro=1013, then R/S gives first the RH% (~76,97%), then Dew Point (~20,68°C)

Thanks for the program! Some background information, however, would be appreciated: e.g. what's about the wet and dry bulbs? Not found in Eddies's blog. Please explain like to a four-year-old toddler. Thanks in advance!

Explanation here
No, Eddie's program does not include wet/dry thermometer, thus "very loosely based" as mentioned.
Eddie has taken the approach that you know the temperature and the RH (relative humidity), of which you can use to calculate the Dew Point. That is, how cold an object in the said environment has to be to form condensation (or dew) on itself. ref a cold beer taken from the fridge will condensate when brought in the hot humid summer.

"In the Olden Dayes" one used (actually, it's occationally still used today, at sea) a "Psychrometer", which is two bulb type (spirit loaded) thermometres where one covered one of them with a small piece of wet cloth over the bulb and the other one left dry. This was flung/waived in the air in order to obtain a temperature difference due to the evaporation of the water from the wet cloth. One then used a Mollière diagram to find the relative humidity in the air.

This program does that without the diagram at hand and in addition, the dew point is calculated, which is not in the Molliére diagram.

"In the Olden Dayes" one used (actually, it's occationally still used today, at sea) a "Psychrometer", which is two bulb type (spirit loaded) thermometres where one covered one of them with a small piece of wet cloth over the bulb and the other one left dry. This was flung/waived in the air in order to obtain a temperature difference due to the evaporation of the water from the wet cloth. One then used a Mollière diagram to find the relative humidity in the air.